Drive System •PDF• •Print• •E-mail•
Drive System Pictures.  Gears hobbed on a mill with a piece of 10 tpi Acme threaded rod with teeth cut out of it.  Clutch and gear wheel machined from HDPE.  
 
Gnashing done with a dremel and thin fiberglass cutoff wheel by hand.  I marked dots on edge of gear using a piece of the all thread material as a gauge.  I don't think being super accurate is important for this level of a job.  They basically give a rough surface for the hob to grab and turn the wheel.
 
The clutch bolts to a split clamp made from 1/2" aluminum.  Inner circles cut with hole saw.  When using a hole saw on HDPE, bring the cutter into the work only long enough to fill the teeth (a couple revolutions), then pull out of the cut, turn drill press off, clean out teeth, then back in again, etc.  Sounds like it would take forever, but it's actually quite quick, and the cuts turn out PERFECT.  Push the drill into the cut too long, and the material in the teeth heats up and cuts grooves in the disk.
 
Hobbing with the all thread hob cuts very clean threads from the leading edge of the cut through the depth of the teeth, but as you can see from the picture it pulls fibers of plastic out the back end of the cut.  I cleaned them up good as I could (which isn't great) but I'm going to call it a 'thread cleaning brush'.  
 
*Update: the gears have been working fine.  I added screw tension adjust inside the center of the tension spring.  Spring pressure alone wasn't satisfactory.
 

 

 

•Profile Information•

Application afterLoad: 0.001 seconds, 0.44 MB
Application afterInitialise: 0.023 seconds, 2.72 MB
Application afterRoute: 0.027 seconds, 3.35 MB
Application afterDispatch: 0.063 seconds, 7.02 MB
Application afterRender: 0.106 seconds, 9.66 MB

•Memory Usage•

10154640

•44 queries logged•

  1. SELECT *
      FROM jos_session
      WHERE session_id = 'k3gevub953ii63r784sc402781'
  2. DELETE
      FROM jos_session
      WHERE ( time < '1561036742' )
  3. SELECT *
      FROM jos_session
      WHERE session_id = 'k3gevub953ii63r784sc402781'
  4. INSERT INTO `jos_session` ( `session_id`,`time`,`username`,`gid`,`guest`,`client_id` )
      VALUES ( 'k3gevub953ii63r784sc402781','1561037642','','0','1','0' )
  5. SELECT *
      FROM jos_components
      WHERE parent = 0
  6. SELECT folder AS type, element AS name, params
      FROM jos_plugins
      WHERE published >= 1
      AND access <= 0
      ORDER BY ordering
  7. SELECT m.*, c.`option` AS component
      FROM jos_menu AS m
      LEFT JOIN jos_components AS c
      ON m.componentid = c.id
      WHERE m.published = 1
      ORDER BY m.sublevel, m.parent, m.ordering
  8. SELECT template
      FROM jos_templates_menu
      WHERE client_id = 0
      AND (menuid = 0 OR menuid = 74)
      ORDER BY menuid DESC
      LIMIT 0, 1
  9. SELECT a.*, u.name AS author, u.usertype, cc.title AS category, s.title AS section, CASE WHEN CHAR_LENGTH(a.alias) THEN CONCAT_WS(":", a.id, a.alias) ELSE a.id END AS slug, CASE WHEN CHAR_LENGTH(cc.alias) THEN CONCAT_WS(":", cc.id, cc.alias) ELSE cc.id END AS catslug, g.name AS groups, s.published AS sec_pub, cc.published AS cat_pub, s.access AS sec_access, cc.access AS cat_access 
      FROM jos_content AS a
      LEFT JOIN jos_categories AS cc
      ON cc.id = a.catid
      LEFT JOIN jos_sections AS s
      ON s.id = cc.section
      AND s.scope = "content"
      LEFT JOIN jos_users AS u
      ON u.id = a.created_by
      LEFT JOIN jos_groups AS g
      ON a.access = g.id
      WHERE a.id = 67
      AND (  ( a.created_by = 0 )    OR  ( a.state = 1
      AND ( a.publish_up = '0000-00-00 00:00:00' OR a.publish_up <= '2019-06-20 13:34:02' )
      AND ( a.publish_down = '0000-00-00 00:00:00' OR a.publish_down >= '2019-06-20 13:34:02' )   )    OR  ( a.state = -1 )  )
  10. UPDATE jos_content
      SET hits = ( hits + 1 )
      WHERE id='67'
  11. SELECT id, title, module, position, content, showtitle, control, params
      FROM jos_modules AS m
      LEFT JOIN jos_modules_menu AS mm
      ON mm.moduleid = m.id
      WHERE m.published = 1
      AND m.access <= 0
      AND m.client_id = 0
      AND ( mm.menuid = 74 OR mm.menuid = 0 )
      ORDER BY position, ordering
  12. SELECT value
      FROM jos_joomlawatch_config
      WHERE name = 'JOOMLAWATCH_LANGUAGE'
      LIMIT 1
  13. SELECT value
      FROM jos_joomlawatch_config
      WHERE name = 'JOOMLAWATCH_LIVE_SITE'
      LIMIT 1
  14. SELECT value
      FROM jos_joomlawatch_config
      WHERE name = 'JOOMLAWATCH_SERVER_URI_KEY'
      LIMIT 1
  15. SELECT value
      FROM jos_joomlawatch_config
      WHERE name='JOOMLAWATCH_IGNORE_IP'
      LIMIT 1
  16. SELECT value
      FROM jos_joomlawatch_config
      WHERE name='JOOMLAWATCH_IGNORE_URI'
      LIMIT 1
  17. SELECT id AS maxid
      FROM jos_joomlawatch
      WHERE browser IS NOT NULL
      ORDER BY id DESC
      LIMIT 1
  18. SELECT value
      FROM jos_joomlawatch_config
      WHERE name = 'JOOMLAWATCH_MAXID_VISITORS'
      LIMIT 1
  19. SELECT ifnull(max(id),0) AS maxFk
      FROM jos_joomlawatch_history
      WHERE browser IS NOT NULL
  20. INSERT IGNORE INTO jos_joomlawatch_history SELECT *
      FROM jos_joomlawatch
      WHERE id > 64311
  21. INSERT IGNORE INTO jos_joomlawatch_uri_history SELECT *
      FROM jos_joomlawatch_uri
      WHERE fk > 64311
  22. SELECT count(ip) AS count
      FROM jos_joomlawatch_blocked
      WHERE ip = '54.209.227.199'
      LIMIT 1
  23. SELECT count(ip) AS count
      FROM jos_joomlawatch_blocked
      WHERE ip LIKE '54.209.227.*%'
      LIMIT 1
  24. SELECT count(ip) AS count
      FROM jos_joomlawatch_blocked
      WHERE ip LIKE '54.209.*%'
      LIMIT 1
  25. SELECT count(ip) AS count
      FROM jos_joomlawatch_blocked
      WHERE ip LIKE '54.*%'
      LIMIT 1
  26. SELECT id, username
      FROM jos_joomlawatch
      WHERE ip = '54.209.227.199'
      LIMIT 1
  27. UPDATE jos_joomlawatch_uri2title
      SET count = count+1, timestamp = '1561037642'
      WHERE (`uri` = '/drive-system.html')
  28. SELECT id
      FROM jos_joomlawatch_uri2title
      WHERE (`uri` = '/drive-system.html')
      LIMIT 1
  29. INSERT INTO jos_joomlawatch (id, ip, country, browser, referer)
      VALUES ('', '54.209.227.199'NULL, NULL, '')
  30. SELECT id
      FROM jos_joomlawatch
      WHERE ip = '54.209.227.199'
      LIMIT 1
  31. INSERT INTO jos_joomlawatch_uri (id, fk, timestamp, uri, title)
      VALUES ('', '64366', '1561037642', '/drive-system.html', 'Drive System')
  32. SELECT value
      FROM jos_joomlawatch_config
      WHERE name = 'JOOMLAWATCH_IP_STATS'
      LIMIT 1
  33. SELECT count(id) AS count
      FROM jos_joomlawatch_info
      WHERE (`group` = '4'
      AND name = '4'
      AND date = '18067')
  34. UPDATE jos_joomlawatch_info
      SET value = value+1
      WHERE (`group` = '4'
      AND name = '4'
      AND date = '18067')
  35. SELECT *
      FROM jos_joomlawatch_goals
  36. SELECT value
      FROM jos_joomlawatch_config
      WHERE name = 'JOOMLAWATCH_LIVE_SITE'
      LIMIT 1
  37. SELECT value
      FROM jos_joomlawatch_config
      WHERE name = 'JOOMLAWATCH_ADFREE'
      LIMIT 1
  38. SELECT value
      FROM jos_joomlawatch_config
      WHERE name = 'JOOMLAWATCH_LIVE_SITE'
      LIMIT 1
  39. SELECT value
      FROM jos_joomlawatch_config
      WHERE name = 'JOOMLAWATCH_ADFREE'
      LIMIT 1
  40. SELECT value
      FROM jos_joomlawatch_config
      WHERE name = 'JOOMLAWATCH_LIVE_SITE'
      LIMIT 1
  41. SELECT value
      FROM jos_joomlawatch_config
      WHERE name = 'JOOMLAWATCH_ADFREE'
      LIMIT 1
  42. SELECT value
      FROM jos_joomlawatch_config
      WHERE name = 'JOOMLAWATCH_LIVE_SITE'
      LIMIT 1
  43. SELECT value
      FROM jos_joomlawatch_config
      WHERE name = 'JOOMLAWATCH_LIVE_SITE'
      LIMIT 1
  44. SELECT value
      FROM jos_joomlawatch_config
      WHERE name = 'JOOMLAWATCH_ADFREE'
      LIMIT 1

•Language Files Loaded•

•Untranslated Strings Diagnostic•

•None•

•Untranslated Strings Designer•

•None•